Sender antenna enveloped by a tubular carrier mast



V UU g -ka ag Feb. 21, 1967 w, KRUGER 3,305,871

SENDER ANTENNA ENVELOPED BY A TUBULAR CARRIER MAST Filed Nov. 6, 1963 United States Patent 3,305,871 SENDER ANTENNA ENVELOPE!) BY A TUBULAR CARRIER MAST Wolfgang Kruger, Munich, Germany, assignor to Siemens & Halslre Aktiengesellschaft Berlin and Munich, a corporation of Germany Filed Nov. 6, E63, Ser. No. 321,735 Claims priority, application Germany, Nov. 12, 1962, S 82,411 7 Claims. (Cl. 343-872) The invention disclosed herein is concerned with a sender antenna enveloped by a tubular mast made of insulating material and is to be considered an improvement on the antenna disclosed in the copending application Ser. No. 189,473, filed April 23, 1962, which is owned by the assignee named in the present case.

The antenna described in the copending application comprises dipole fields disposed within a tubular mast made of insulating material and serving as a carrier and weather protection therefor, the hollow insulating body forming the mast being reinforced by inserts which are respectively embedded Within or surrounded by the insulating material.

The object of the present invention is to improve the mechanical stability of the hollow insulating body by appropriately constructing the reinforcing inserts.

According to the invention, this object is realized by the provision of reinforcing inserts which are made in the form of cross-sectionally arcuate or sickle-shaped shells extending parallel to the longitudinal axis of the hollow insulating body forming the tubular carrier mast. This measure makes it possible to construct a tubular insulating mody of exteriorly simple configuration, with decreased wall thickness and increased stability against bending stresses and the formation of dents. A plurality of such cross-sectionally arcuately shaped shell are advantageously uniformly distributed in angular positions throughout the cylindrical tubular insulating body.

According to another feature of the invention, the radiators may be so arranged with respect to the wall of the tubular insulating body that they lie, as seen in the main radiation directions, respectively opposite the wall parts with the least thickness.

The construction of the tubular insulating material cylinder is advantageously effected by applying the prefabricated cross-sectionally arcuate shells to the inner wall which is made of a plurality of fabric layers and covering the shells by further outer fabric layers, so that they are on all sides surrounded by such layers.

The arcuately shaped shells are appropriately made of fiber glass layers which are connected by epoxyor polyester resin. The fabric layers, between which the arcuately shaped shells are disposed, are advantageously made of the same material, namely, synthetic fiber glass material, as the shells.

Fuither details of the invention will appear from the appended claims and from the description of an embodiment which is rendered below with reference to the accompanying drawing showing parts of a sender antenna operating in the decimeter wave range.

FIG. 1 shows in cross-sectional representation an omnidirectional antenna disposed within a tubular insulating material envelope serving as a carrier therefor;

FlG. 2 shows in cross-sectional representation details of a flange which is part of a tubular insulating material cylinder and serves for connecting adjacent cylinders together; and

FIG. 3 shows in perspective view a cross-seetionally arcuately shaped shell serving as a reinforcing insert.

The omnidirectional antenna according to FIG. 1 comprises four dipole radiator assemblies 1 to 4 which are disposed in quadratic arrangement and in suitable manher (not shown) fastened to the inner wall of the tubular insulating material carrier 5. The antennas which are appropriately fed in rotary field, serve for producing an omnidirectional radiation diagram. The enveloping wall 5 comprises an outer sheath 5a and an inner sheath 511, such sheaths being respectively composed of a plurality of wound fabric layers consisting of fiber glass, which are bonded together by saturation with a suitable binder. Between the outer sheath 5a and the inner sheath 5b are arranged four cross-sectionally arcuately or crescent shaped reinforcing shells 6 to 9, which are angularly uniformly distributed, providing a reinforcing for the wall of the tubular insulating material body and particularly increasing its stability with respect to bending stresses and its stability against formation of dents. The sheaths 5a and 5b are formed by winding the corresponding fabric layers, the insert shells being placed in position on the Wound inner sheath 5b and the fabric layers forming the outer sheath 5a being wound thereabout, thus embedding the arcuate shells between the sheaths. The wall thickness can thus be held relatively small and therefore affects the radiation only slightly. The arcuately shaped shells 6 to it are with respect to the dipole fields 1 to 4 angularly so arranged that the main radiation directions of the dipole fields lie in the regions of the thinnest wall sections of the tubular insulating cylinder 5. This is obtained by disposing the arcuately shaped shells substantially in the direction of the diagonals of the polygonal arrangement formed by the dipole radiator assemblies 3 to 4. The lateral extent-as part of the angular disposition-of the reinforcing shells 6 to 9, which extend in longitudinal direction of the tubular insulating material cylinder 5 is, with respect to the number thereof so selected, that they do not mutually overlap and that the wall thickness is in given regions merely formed by the sheaths 5a an-d'Sb.

Since the tubular mast is formed of a plurality of vertically successively arranged insulating mate-rial cylinders, as described in the previously noted copending application, it is necessary to provide at the junctures of the individual cylinders suitable fastening means in the form of flanges or the like. FIG. 2 shows in cross-sectional representation the construction of such a flange 10 at the end of a tubular insulating material cylinder, the section being taken along a line intersecting an arcuate reinforcing insert 6. The outer fabric sheath 5a is thicker in the region of the flan e and is, just as the inner fabric sheath 5b, bent radially inwardly. The arcuate shell 6 may terminate at the region of the thickened flange, as shown, or may likewise be bent radially inwardly. The flange is on the inside reinforced by means of a crosssectionally L-shaped ring lit. Suitable bores are formed in the radially inwardly extending parts, for extending therethrough fastening elements, for example, screws or rivets serving for connecting together adjacent insulating material cylinders.

FIG. 3 shows one of the insulating material reinforcing shells, for example, the shell 6, which has throughout its extent approximately the same cross-section and a curvature which matches the curvature of the respective insulating material cylinder into which it is to be inserted.

Changes may be made within the scope and spirit of the appended claims which define what is believed to be new and desired to have protected by Letters Patent.

I claim:

1. A sender antenna enveloped by a tubular mast serving as a carrier and as weather protection for antenna elements which are fastened to the inner Wall thereof, said tubular mast being constructed as a tubular insulating body with the wall thereof being formed by an outer and an inner sheath, generally concentrically disposed and wound of insulating material layers, and cross-sectionally crescent-shaped reinforcing inserts, which are prefabricated parts extending parallel to the longitudinal axis of said tubular insulating body and angularly uniformly distributed throughout such wall with such inserts being embedded between said sheaths, said antenna elements being so arranged with respect to the wall of said tubular insulating body that the main radiation directions extend through wall portions of minimum thickness.

2. A sender antenna according to claim 1, wherein said antenna elements are dipole radiators arranged in polygonal configuration and being fed in rotary field.

3. A sender antenna according to claim 1, wherein said cross-sectionally arcuately shaped reinforcing inserts are made of fiber glass layers bonded by epoxy and/ or polyester resins.

4. A sender antenna according to claim 1, wherein said sheaths and said cross-sectionally arcuately shaped reinforcing inserts are made of layers of identical insulating material bonded together by identical binder means.

5. A sender antenna according to claim 1, wherein said sheaths and said cross-sectionally arcuately shaped reinforcing inserts are made of layers of fiber glass bonded by epoxy and/ or polyester resin.

6. A sender antenna according to claim 1, wherein the edges of the respective reinforcing inserts are angularly spaced from one another, the resulting spaces being bridged by relatively thin wall portions of said tubular insulating body which portions are composed solely of the respective outer and inner sheaths.

7. A sender antenna enveloped by a tubular mast serving as a carrier and as weather protection for antenna elements which are fastened to the inner Wall thereof, said tubular mast being constructed as a tubular insulating body with the wall thereof being formed by an outer and an inner sheath wound of insulating material layers, and cross-sectionally arcuate shell-like reinforcing inserts, which are prefabricated parts extending parallel to the longitudinal axis of said tubular insulating body and angularly uniformly distributed throughout such wall with such inserts being embedded between said sheaths, the edges of the respective reinforcing inserts being angularly spaced from one another, the resulting spaces being bridged by relatively thin wall portions of said tubular insulating body which are composed solely of the respective outer and inner sheaths, said antenna elements being so disposed that the main radiation directions thereof extend through said relatively thin wall portion.

References Cited by the Examiner UNITED STATES PATENTS 2,413,085 12/1946 Tiley 343-800 2,607,009 8/1952 Affel 343-872 2,631,237 3/1953 Sicbak et a1. 343800 X 3,039,100 6/1962 Kay 343872 3,252,161 5/1966 Gottwald et a1. 343797 FOREIGN PATENTS 1,236,873 6/1960 France.

HERMAN KARL SAALBACH, Primary Examiner.

E. LIEBERMAN, C. BARAFF, Assistant Examiners. 

1. A SENDER ANTENNA ENVELOPED BY A TUBULAR MAST SERVING AS A CARRIER AND AS WEATHER PROTECTION FOR ANTENNA ELEMENTS WHICH ARE FASTENED TO THE INNER WALL THEREOF, SAID TUBULAR MAST BEING CONSTRUCTED AS A TUBULAR INSULATING BODY WITH THE WALL THEREOF BEING FORMED BY AN OUTER AND AN INNER SHEATH, GENERALLY CONCENTRICALLY DISPOSED AND WOUND OF INSULATING MATERIAL LAYERS, AND CROSS-SECTIONALLY CRESCENT-SHAPED REINFORCING INSERTS, WHICH ARE PREFABRICATED PARTS EXTENDING PARALLEL TO THE LONGITUDINAL AXIS OF 